Biographies for the very young can be a tricky business. In this absorbing account of the great composer's life, Isadora (Lili at Ballet) adroitly navigates the potential hazards--oversimplification, stilted prose, a yawn-inspiring excess of detail, to name just a few. Keenly attuned to her audience, she demonstrates both a simplicity of focus and an artist's eye for detail, selecting scenes and elements in Mozart's life of most interest to children, such as little three-year-old Wolfgang bursting into tears when he sounded out a wrong note on the clavier, or the pet starling that sometimes sang along with the grown-up Mozart and his own children many years later. Serene watercolors provide an almost impressionistic backdrop to the unfolding events; like stage sets for one of Mozart's operas, they serve to give readers a strongly rooted sense of place, both in terms of historical setting as well as era. Ages 3-8. (Apr.)